Intersubband relaxation in modulation-doped multiple quantum well structures

J. L. Educato, A. Sugg, Jean-Pierre Leburton

Research output: Chapter in Book/Report/Conference proceedingConference contribution


A thoretical investigation of the time constants of intersubband transitions in n-type GaAs/Alx Ga1-x As modulation-doped multi-quantum-well (MD MQW) structures by emission of polar optical phonons is presented. It is shown that the space charge resulting from positively ionized donors induces conduction band minima in the barriers that contain several bound states. In narrow wells, the upper subband interacts with the eigenstates of the barrier and causes a delocalization of the upper subband wave function into the AlGaAs barrier. This interaction leads to increasing probability for excited carriers to reside in the barriers and relax to the ground state with emission of AlGaAs LO phonons. Thus transition rates to the ground state are calculated for both wells and barriers. Although experimental and theoretical lifetimes are slightly different, the factor of 2 decrease in relaxation time seen experimentally is also predicted theoretically.

Original languageEnglish (US)
Title of host publicationQuantum Electron Laser Sci Conf
Editors Anon
PublisherPubl by IEEE
Number of pages2
StatePublished - 1989
EventQuantum Electronics and Laser Science Conference - Baltimore, MD, USA
Duration: Apr 24 1989Apr 28 1989


OtherQuantum Electronics and Laser Science Conference
CityBaltimore, MD, USA

ASJC Scopus subject areas

  • General Engineering

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